The voltage sensitive calcium channel as the transducer of electrical events into chemical events has a unique role in central nervous system function. Understanding the development of this channel is essential to the pathophysiology of many diseases, for example hypoxic-ischemic neuronal damage and the increased incidence of seizure during the first year of life. Using unique new neuropeptide probes from the Conus marine snail, detection of changes in calcium channel number, type and structure will be studied in developing human brain pathology specimens. Toxin binding, block of calcium45 uptake in synaptosomes and gel electrophoresis after crosslinking to toxin will be used to characterize Ca channels. Data from chick and mouse brain samples will be compared to human brain results. The voltage sensitive release of the excitatory neurotransmitted glutamate as well as the pharmacologic effect of the calcium channel blocker on glutamate release will also be studied.